Brain edema is the accumulation of fluid in the brain and resultant swelling of the brain. Causes of brain edema may include trauma, a tumor, exposure to toxic substances, and other injuries. About 1.7 million people in an average year in the U.S. incur a head injury requiring medical care and about 38,000 die from head injury before being admitted to a hospital.
Brain damage may also be the result of a lack of oxygen. For instance, hypoxic-ischemic encephalopathy, or HIE, is a condition that occurs when the brain has been deprived of an adequate oxygen supply. Infants that have incured hypoxic-ischemic encephallopathy (HIE) constitute about 23% of neonatal deaths worldwide.
Current clinical practice for the treatment of brain edema cases is to use an invasive procedure called craniotomy. Experimental evidence for the beneficial or detrimental role of decompression craniotomy after traumatic brain injury are scarce. Recent researches and studies on mice suggest that a craniotomy may be a useful therapeutic option after traumatic brain injury (TBI) in humans, provided that it is applied early.
In infants with hypoxic-ishemic encephalopathy, therapeutic hypothermia is more beneficial for edema reduction if applied early. In spite of improvements in outcome since the introduction of therapeutic hypothermia as a treatment modality, 55% of treated infants die or have adverse neurodevelopmental outcomes. Additional neuroprotective strategies are needed for improving the outcomes of affected infants.
The detection of edema may be based on computed tomography (CT) scans or magnetic resonance imaging (MRI). However, since both CT and MRI are expensive, not every medical facility has such equipment. Also, since such equipment is not portable and CT has radiation exposure, such equipment cannot be used in the field or for continuous, bedside monitoring. Once edema is detected, its progression is usually monitored by using an intracranial pressure (ICP) monitoring sensor which is invasive and can cause complications.
Early detection of brain edema can help clinicians in the timely identification of patients that are in need of surgery or other types of therapy and thus, improve the outcome of such therapies. Thus, early detection of brain edema may be effective for reducing the development of more serious brain injury and related disabilities and can lessen the costs of treating a brain injury.
In addition, the ability to monitor cerebral autoregulation may provide important information for the care of some patients. Cerebral autoregulation is the physiological mechanism that maintains cerebral blood flow at an appropriate level during changes in blood pressure. By way of example, an accurate assessment of cerebral autoregulation may guide in the selection and level of treatment regimes from mild to intense using hypothermia to drug treatments and hence improve treatment outcomes and quality of life of patients.